The eclipse command lwjitter can be used as a way to quickly
reduce the data. The command uses an initialisation file, which
contains parameters that define how the recipe runs. To generate one,
type lwjitter -g lwjitter.ini at the prompt and this will create
an initialisation file called lwjitter.ini. This file can be edited
and modified by the user to setup some parameters.

The recipe reduces data by:

classifying the input frames into those taken with the secondary at either
side of the nod, i.e. positions A and B.

computing (A-B)/2. Each frame shows one positive and two negative objects.

computing the offsets between frames. Initial estimates are taken from the
FITS headers and further refined through cross-correlation.